williston: Kansas pterodactyls. ii 



ilium and femur, as also the ribs, show that they hold their natural 

 relations to the pectoral arch. The tail, alone, can not be got at. 



Extreme expanse of wing-bones 2400 mm 7 ft. 10 in. 



Expanse of wings in life, approximated. 2000 6 6 



Length of head, estimated 150 6 



Length of neck 128 ^j4 



Length of trunk 165 6^4 



Length of leg and foot, outstretched ....275 11 



But one species has been described from the American Cretaceous 

 smaller than the present one, Pteranodon tiamis Marsh, in which the 

 expanse of wings is given as not more than three or four feet. In 

 this estimate the author is certainly in error. The size of the hum- 

 erus, as given, is rather more than three-fourths that of the present 

 species, and the expanse, hence, must be nearly five feet in life, or six 

 feet as the bones lie outstretched. 



As regards the specific determination of the present specimen, there 

 must necessarily be some doubt until the species already named have 

 been recognizably described. But three of the existing species can be 

 taken into account, JV. gracilis, P. comptus and P. nanus. That it can 

 not be the last, has already been shown. In size, it agrees well with 

 P. comptus, but the other characters throw no light upon the identity. 

 The measurements given of the type specimen of N. gracilis show 

 the size to be materially greater, — a character, however, of subordinate 

 value — greater slenderness, and a relatively shorter first wing-phalanx. 

 The relative lengths of wing-metacarpals, wing-phalanx and ulna in 

 N. gracilis and the present specimen may be expressed as follows : 



Length of wing-metacarpal 100 .... 100 



Length of first wing-phalanx 115. 6. ...11 9. 5 



Length of ulna 62.3 .... 60. 4 



It will be seen that not a single character has yet been given to dis- 

 dinguish the genus from Pterodactylus, and it is not at all impossible 

 that it may prove to be the same ; its location among the Pteranodon- 

 tidae rests solely on the assumed absence of teeth, and that is a 

 character yet wholly unknown. 



The material now in the museum permits a fuller discussion of the 

 relations and characters of this group of reptiles than has been hither- 

 to attempted. Originally, they were described as constituting a new 

 order, a view still held by its author and no one else. Lydekker, in 

 his Paleontology and Catalogue gives them a subordinal value; Zittel 

 only a family value, though expressing doubt as to their subordinal 

 rank. 



It seems very probable that the genus Nyctodaciylus has no teeth in 



